The theme is now public. I also wrote README explainig how to use this theme.
Chyrp pretty much died (last update in 2016), Chyrp Lite’s codebase is too different at this point (I have custom feathers, custom image processing and probably a few other things, and I don’t remember at all how I did any of it), and having a website with an outdated CMS is a major security hole. I’ve heard of Jekyll, but hadn’t thought much about Static Site Generators until I encountered Erik McClure’s website (through a link to Pony Clicker). I saw what he did with his blog, though about what I needed for my blog and eventually decided to migrate to a static website. I had a choice between Jekyll and Hugo. Jekyll required a Ruby environment and had some dependencies, while Hugo was written in Go and was compiled into a single binary. Also SlackBuilds had Hugo and didn’t have Jekyll. So Hugo it is.